Method for adjusting a papermaking process to extend the operating life of a papermaking belt

ABSTRACT

A method for adjusting a papermaking process for producing rolls of convolutely wound web material having a machine direction (MD) and a cross-machine direction (CD) coplanar and orthogonal thereto is disclosed. The process improves the operating life of a papermaking belt used therefor.

FIELD OF THE INVENTION

The present disclosure generally relates to processes useful in makingstrong, soft, absorbent paper products. More particularly, the presentdisclosure relates to papermaking processes using belts formed from aresinous framework and a reinforcing structure having embedded sensorsthat provide process feedback that can provide a significant increase inthe operating lifetime of the papermaking belt.

BACKGROUND OF THE INVENTION

Processes for the manufacturing of paper products for use in tissue,toweling and sanitary products generally involve the preparation of anaqueous slurry of paper fibers and then subsequently removing the waterfrom the slurry while contemporaneously rearranging the fibers in theslurry to form a paper web. Various types of machinery can be employedto assist in the dewatering process.

The processes to manufacture these paper products use a paper slurrythat is fed onto the top surface of a traveling endless belt that servesas the initial papermaking surface of the machine. These papermakingbelts or fabrics carry various names depending on their intended use.Fourdrinier wires, also known as Fourdrinier belts, forming wires, orforming fabrics are used in the initial forming zone of the papermakingmachine. Dryer fabrics carry the paper web through the drying operationof the papermaking machine.

One particular papermaking belt utilizes a foraminous woven membersurrounded by a hardened photosensitive resin framework. The resinframework has a plurality of discrete, isolated, channels known as“deflection conduits” disposed therein. The process to manufacture apaper product can involve the steps of associating an embryonic web ofpapermaking fibers with the top surface of the papermaking belt,deflecting the paper fibers into the deflection conduits, and applying avacuum or other fluid pressure differential to the web from the backside(machine-contacting side) of the papermaking belt. This process made itfinally possible to create paper having certain desired preselectedcharacteristics.

Although the aforementioned process produces suitable papermaking beltsand results in superior formed paper products, it has been found thatthe papermaking manufacturing environment severely limits the lifetimeof these papermaking belts. This could be attributed to the inability tomeasure certain key physical parameters of the papermaking belt duringuse. By way of example, the equipment used in the manufacture of paperproducts subjects the papermaking belt to extreme temperatures, bendingmoments, tensions, stress, strain, pH, wear, and the like. Each of thesefactors has been found to severely limit the life of the papermakingbelts by causing micro-fractures to occur in the hardened resins thatform the surface of the papermaking belt as well as fractures due tooxidation and decay of the resin itself. Without desiring to be bound bytheory, resin loss is believed to be the primary cause of belt failure.This is particularly true of papermaking systems that incorporate theuse of high temperature pre-dryers and Yankee drying drums.Additionally, the high pressures experienced by the papermaking belt inprocess nips (formed between pressure rolls) and vacuum slots, as wellas process abrasion points (e.g., while traversing vacuum boxes and thelike) and stresses introduced by misaligned process equipment have beenlinked to premature papermaking belt failures.

The significance of the difficulties experienced by users of thesepapermaking belts is exacerbatingly increased by the relatively highcost of the papermaking belts themselves. For example, manufacturing aforaminous woven element that is incorporated into these belts requiresexpensive textile processing operations, including the use of large andcostly looms. Also, substantial quantities of relatively expensivefilaments are incorporated into these foraminous woven elements. Thecost of these papermaking belts is further increased when filamentshaving high heat resistance properties are used. These special filamentsare generally necessary for papermaking belts that pass through varioushigh temperature drying operations.

In addition to the cost of the belt itself, the decay and/or failure ofa papermaking belt can also have serious implications on the efficiencyof the papermaking process and the paper products so produced. A highfrequency of paper machine belt failures can substantially affect theeconomies of a paper manufacturing business due to the loss of the useof the expensive papermaking machinery (that is, the machine “downtime”)during the time a replacement belt is being fitted on the papermakingmachine.

Therefore, a need exists for an improved papermaking belt, a method ofmaking a papermaking belt, and an ability to monitor the physicalcondition of a papermaking belt during use in the production of paperproducts that can eliminate the foregoing problems. In short, theability to measure the physical condition of the papermaking belt madeby the prior processes during use can provide for real-time in situfeedback into the papermaking process that can stimulate process changesnecessary to produce quality paper products and simultaneously increasepapermaking belt life.

SUMMARY OF THE INVENTION

The present disclosure provides for a process for adjusting apapermaking process for producing rolls of convolutely wound webmaterial having a machine direction (MD) and a cross-machine direction(CD) coplanar and orthogonal thereto. The process improves the operatinglife of a papermaking belt used therefor. The process for adjusting thepapermaking process comprising the steps of: (a) providing a foraminouspapermaking belt having a discrete measuring device disposed therein;(b) providing a papermaking machine, said papermaking machine having atleast one heating process, said heating process having a heating processset-point, said foraminous papermaking belt being integral with saidpapermaking machine; (c) depositing an aqueous dispersion of papermakingfibers upon a surface of said papermaking belt; (d) dewatering saidaqueous dispersion of papermaking fibers while disposed upon saidsurface of said foraminous papermaking belt by causing said foraminouspapermaking belt and said aqueous dispersion of papermaking fibersdisposed thereon to traverse through said heating process, said discretemeasuring device measuring a temperature of said heating process; (e)causing said foraminous papermaking belt to traverse past a receiver,said receiver being in wireless communicating engagement with saiddiscrete measuring device when said discrete measuring device isproximate said receiver, said discrete measuring device being capable ofwirelessly transmitting information to said receiver, said informationcomprising data relating to said temperature of said heating processduring said dewatering step; and, (f) changing said heating processset-point according to said measurement of said temperature of saidheating process of said dewatering step.

The present disclosure also provides for adjusting a papermaking processfor producing rolls of convolutely wound web material having a machinedirection (MD) and a cross-machine direction (CD) coplanar andorthogonal thereto. The process improves the operating life of apapermaking belt used therefor. The process for adjusting thepapermaking process comprising the steps of: (a) providing a foraminouspapermaking belt having a discrete measuring device disposed therein;(b) providing a papermaking machine, said papermaking machine having atleast one compressionary process, said compressionary process having acompressionary process set-point, said foraminous papermaking belt beingintegral with said papermaking machine; (c) depositing an aqueousdispersion of papermaking fibers upon a surface of said papermakingbelt; (d) dewatering said aqueous dispersion of papermaking fibers whiledisposed upon said surface of said foraminous papermaking belt bycausing said foraminous papermaking belt and said aqueous dispersion ofpapermaking fibers disposed thereon to traverse through saidcompressionary process, said discrete measuring device measuring atleast one compressionary force of said compressionary process; (e)causing said foraminous papermaking belt to traverse past a receiver,said receiver being in wireless communicating engagement with saiddiscrete measuring device when said discrete measuring device isproximate said receiver, said discrete measuring device being capable ofwirelessly transmitting information to said receiver, said informationcomprising data relating to said pressure of said compressionary processduring said dewatering step; and, (f) changing said compressionaryprocess set-point according to said measurement of said pressure of saidcompressionary process of said dewatering step.

The present disclosure further provides for a process for adjusting apapermaking process for producing rolls of convolutely wound webmaterial having a machine direction (MD) and a cross-machine direction(CD) coplanar and orthogonal thereto. The process improves the operatinglife of a papermaking belt used therefor. The process for adjusting thepapermaking process comprising the steps of: (a) providing a foraminouspapermaking belt having a discrete measuring device disposed therein;(b) providing a papermaking machine, said papermaking machine having atleast one papermaking belt deformation process, said papermaking beltdeformation process having a papermaking belt deformation characteristicset-point, said foraminous papermaking belt being integral with saidpapermaking machine; (c) depositing an aqueous dispersion of papermakingfibers upon a surface of said papermaking belt; (d) dewatering saidaqueous dispersion of papermaking fibers while disposed upon saidsurface of said foraminous papermaking belt by causing said foraminouspapermaking belt and said aqueous dispersion of papermaking fibersdisposed thereon to traverse through said papermaking belt deformationprocess, said discrete measuring device measuring at least onepapermaking belt deformation characteristic of said papermaking beltdeformation process; (e) causing said foraminous papermaking belt totraverse past a receiver, said receiver being in wireless communicatingengagement with said discrete measuring device when said discretemeasuring device is proximate said receiver, said discrete measuringdevice being capable of wirelessly transmitting information to saidreceiver, said information comprising data relating to said papermakingbelt deformation characteristic of said papermaking belt deformationprocess during said dewatering step; and, (f) changing said papermakingbelt deformation characteristic process set-point according to saidmeasurement of said pressure of said papermaking belt deformationprocess of said dewatering step.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of one embodiment of a continuouspapermaking machine useful in carrying out the process of thisdisclosure;

FIG. 2 is a plan view of a portion of an embodiment of the improvedpapermaking belt of the present disclosure;

FIG. 3 is an enlarged cross-sectional view of the portion of theimproved papermaking belt shown in FIG. 2 taken along line 3-3;

FIG. 4 is an enlarged cross-sectional view of the portion of theimproved papermaking belt shown in FIG. 2 taken along line 4-4;

FIG. 5 is an enlarged plan view of a portion of an exemplary wovenmulti-layer reinforcing structure suitable for use with the improvedpapermaking belt;

FIG. 6 is a schematic representation of the basic apparatus for makingthe papermaking belt of the present disclosure;

FIG. 7 is an enlarged schematic cross-sectional view of a portion of thecasting surface of a process for making the papermaking belt of thepresent disclosure showing the working surface, barrier film,reinforcing structure, resin, and mask.

DETAILED DESCRIPTION

In papermaking, the term “machine direction” (MD) refers to thatdirection which is parallel to the flow of the paper web through theequipment. The “cross-machine direction” (CD) is perpendicular to themachine direction. The “Z-direction” refers to that direction that isorthogonal to both the MD and CD.

The Improved Papermaking Belt

In the representative papermaking machine illustrated in FIG. 1, thepapermaking belt 10 (or belt 10) of the present disclosure can take theform of an endless belt. In FIG. 1, the papermaking belt 10 carries apaper web (“fiber web” or the like) in various stages of its formationand travels in the direction indicated by directional arrow B around thepapermaking belt return rolls 19 a, 19 b, impression nip roll 20,papermaking belt return rolls 19 c, 19 d, 19 e and 19 f, and emulsiondistributing roll 21. The loop the papermaking belt 10 travels aroundincludes a means for applying a fluid pressure differential to the paperweb, such as vacuum pickup shoe 24 a and multi-slot vacuum box 24. InFIG. 1, the papermaking belt can also travel around a pre-dryer such asblow-through dryer 26, and pass between a nip formed by the impressionnip roll 20 and a Yankee dryer drum 28. Although an embodiment of thepresent disclosure is in the form of an endless belt, the presentdisclosure can be incorporated into numerous other forms.

The overall characteristics of the papermaking belt 10 of the presentdisclosure are shown in FIGS. 2-4. The papermaking belt 10 of thepresent disclosure is generally comprised of two primary elements: aframework 32 and a reinforcing structure 33. In one non-limitingexample, framework 32 can be a hardened polymeric photosensitive resin.In one embodiment, the papermaking belt 10 is provided as an endlessbelt having two opposed surfaces which are referred to herein as thepaper-contacting side 11 and a textured backside or simply, backside 12.The backside 12 of the papermaking belt 10 contacts the machineryemployed in the papermaking operation, such as vacuum pickup shoe 24 aand multi-slot vacuum box 24. The framework 32 has a first surface 34, asecond surface 35 opposite the first surface 34, and conduits 36extending between the first surface 34 and the second surface 35. Thefirst surface 34 of the framework 32 contacts the fiber webs to bedewatered, and defines the paper-contacting side 11 of the belt. Theconduits 36 extending between the first surface 34 and the secondsurface 35 channel water from the fiber web that rests on the firstsurface 34 to the second surface 35 and provides areas into which thefibers of the fiber web can be deflected into and rearranged. FIG. 2shows that the network 32 a can comprise the solid portion of theframework 32 that surrounds the conduits 36 to define a net-likepattern.

As shown in FIG. 2, the openings 42 of the conduits 36 can be arrangedin a preselected pattern in the network 32 a. FIG. 2 shows that thefirst surface 34 of the framework 32 has a paper side network 34 aformed therein which surrounds and defines the openings 42 of theconduits 36 in the first surface 34 of the framework 32. The secondsurface 35 of the framework 32 has a backside network 35 a thatsurrounds and defines the openings 43 of the conduits 36 in the secondsurface 35 of the framework 32. FIGS. 3-4 provide that the reinforcingstructure 33 of the papermaking belt 10 is at least partially surroundedby, enveloped, embedded, and/or encased within the framework 32. Morespecifically, the reinforcing structure 33 is positioned between thefirst surface 34 of the framework 32 and at least a portion of thesecond surface 35 of the framework 32. FIGS. 3 and 4 also show that thereinforcing structure 33 has a paper-facing side 51 and a machine-facingside 52 opposed thereto. As shown in FIG. 2, the reinforcing structure33 has interstices 39 and a reinforcing component 40. The reinforcingcomponent 40 comprises the portions of the reinforcing structureexclusive of the interstices 39 (that is, the solid portion of thereinforcing structure 33). A plurality of measurement device(s) 50 (alsoreferred to herein as measuring device(s) 50) can be disposed within theframework 32 and can be incorporated into or upon the reinforcingstructure 33. Measurement devices 50, their incorporation into apapermaking belt, and their usefulness will be discussed infra.

The reinforcing component 40 is generally comprised of a plurality ofstructural components 40 a. FIGS. 3-4 show that the second surface 35 ofthe framework 32 has a backside network 35 a with a plurality ofpassageways 37. The passageways 37 allow air to enter between thebackside surface 12 of the papermaking belt 10 and the surfaces of thevacuum dewatering equipment employed n the papermaking process (such asvacuum pickup shoe 24 a and vacuum box 24) when a vacuum is applied bythe dewatering equipment to the backside 12 of the belt to deflect thefibers into the conduits 36 of the belt 10.

The paper-contacting side 11 of the belt 10 shown in FIGS. 1-4 is thesurface of the papermaking belt 10 which contacts the paper web which isto be dewatered and rearranged into the finished product. Thepaper-contacting side 11 of the belt 10 may also be referred to as the“embryonic web-contacting surface” of the belt 10. As shown in FIGS.2-4, the paper-contacting side 11 of the belt 10 is generally formedentirely by the first surface 34 of the framework 32.

As shown in FIG. 1, the backside 32 is the surface which travels overand is generally in contact with the papermaking machinery employed inthe papermaking process.

The reinforcing structure 33 is shown in FIGS. 2-4 and in isolation inFIG. 5. The reinforcing structure 33 strengthens the resin framework 32and has suitable projected open area to allow the vacuum dewateringmachinery employed in the papermaking process to adequately perform itsfunction of removing water from partially-formed webs of paper and topermit water removed from the paper web to pass through the papermakingbelt 10. The reinforcing structure 33 can comprise a woven element (alsosometimes referred to herein as a woven “fabric”), a nonwoven element, ascreen, a net (for instance, thermoplastic netting), a scrim, or a bandor plate (made of metal or plastic or other suitable material) with aplurality of holes punched or drilled in it provided the reinforcingstructure 33 adequately reinforces the framework 32 and has sufficientprojected open area. Preferably, the reinforcing structure 33 comprisesa foraminous woven element.

Generally, as shown in FIGS. 2-5, the reinforcing structure 33 comprisesa reinforcing component 40 and a plurality of interstices 39. Thereinforcing component 40 is the portion of the reinforcing structure 33exclusive of the interstices 39. In other words, the reinforcingcomponent 40 is the solid portion of the reinforcing structure 33. Thereinforcing component 40 is comprised of one or more structuralcomponents 40 a. “Structural components” refers to the individualstructural elements that comprise the reinforcing structure 33.

The interstices 39 allow fluids (e.g., water removed from the paper web)to pass through the belt 10. The interstices 39 may form any pattern inthe reinforcing structure 33. The pattern formed by the interstices 39should be contrasted with the preselected pattern formed by the conduitopenings.

As shown in FIGS. 3-4, the reinforcing structure 33 has two sides. Theseare the paper-facing side (or “paper support side”) 51 that faces thefiber webs to be dewatered, and the machine-facing side (or “rollercontact side”) generally designated 52 opposing the paper-facing side.As shown in FIGS. 3 and 4, the reinforcing structure 33 is positionedbetween the first surface 34 of the framework 32 and at least a portionof the second surface 35 of the framework 32.

The structural components 40 a of a woven reinforcing structure cancomprise yarns, strands, filaments, or threads. It is also to beunderstood that the above terms (yarns, strands, etc.) could comprisenot only monofilament elements, but also multifilament and/ormulti-component (e.g., bi-component) elements. Many types of wovenelements are suitable for use as a reinforcing structure 33 in thepapermaking belt 10 of the present disclosure. Suitable woven elementsinclude foraminous monolayer woven elements (having a single set ofstrands running in each direction and a plurality of openingstherebetween) such as the reinforcing structure 33 shown in FIG. 5.

The papermaking belt 10 comes under considerable stress in the machinedirection due to the repeated travel of the belt 10 over the papermakingmachinery in the machine direction and also due to the heat transferredto the belt by the drying mechanisms employed in the papermakingprocess. Such heat and stress can cause the papermaking belt to stretch.If the papermaking belt 10 stretches significantly, its ability to serveits intended function of carrying a paper web through the papermakingprocess can become diminished to the point of uselessness. Ifsignificant tension is applied to the papermaking belt 10 duringmanufacture of the papermaking belt 10 itself or during use of thepapermaking belt 10 on a paper machine, mechanical failure can occur(i.e., the belt can rip or can be caused to sufficiently narrow (Poissoneffect)).

To be suitable for use as a reinforcing structure, a multilayer wovenelement preferably has some type of structure that provides forreinforcement of the machine direction yarns 53. In other words, themultilayer fabric should have increased fabric stability in themachine-direction.

As shown in FIGS. 2-5, a preferred reinforcing structure 33 is amultilayer woven element that has a single layer yarn system with yarnswhich extend in a first direction and a multiple layer yarn system withyarns which extend in a second direction normal to the first direction.In the preferred reinforcing structure 33, the first direction is thecross-machine direction. The yarns that extend in the first directioncomprise the weft yarns 54. The multiple layer yarn system extends inthe machine direction. Fabrics having multiple machine direction warpyarns are preferred, however, because the additional strands run in thedirection which is generally subject to the greatest stresses.

While the specific materials of construction of the warp yarns and weftyarns can vary, the material comprising the yarns should be such thatthe yarns will be capable of reinforcing the resinous framework andsustaining stresses as well as repeated heating and cooling withoutexcessive stretching. Suitable materials from which the yarns can beconstructed include polyesters, polyamides, high heat resistantmaterials such as KEVLAR™, NOMEXTm, combinations thereof, and any othermaterials which are known for use in papermaking fabrics.

Any convenient cross-sectional dimensions (or size) of the yarns can beused as long as the flow of air and water through the conduits 36 is notsignificantly hampered during the paper web processing and as long asthe integrity of the papermaking belt 10 maintained. The cross-sectionalshapes of the yarns in the different layers and yarn systems can alsovary between the layers and yarn systems.

The reinforcing structure 30 can have a first portion P₀₁ of thereinforcing component 40 that has a first opacity 0 ₁, and a secondportion P₀₂ of the reinforcing component 40 that has a second opacity 0₂. The two opacities 0 ₁ and 0 ₂ can be related such that the secondopacity 0 ₂ is less (that is, relatively less opaque) than the firstopacity 0 ₁. The first opacity 0 ₁ should be sufficient to substantiallyprevent the curing of a photosensitive resinous material, if such amaterial is used to form the framework 32, when that photosensitiveresinous material is in its uncured state and the first portion P₀₁ ispositioned between the photosensitive resinous material and a source ofactinic radiation.

The framework 32 can be formed by manipulating a mass of material,generally in liquid form, so that the material, when in solid form, atleast partially surrounds the reinforcing structure 33 so that thereinforcing structure 33 is positioned between the first surface 34 andat least a portion of the second surface 35 of the framework 32. Thematerial can be manipulated so that the framework 32 has a plurality ofconduits 36 or channels that extend between the first surface 34 and thesecond surface 35 of the framework 32. The material can also bemanipulated so that the first surface has a paper side network 34 aformed therein which surrounds and defines the openings of the conduits36 in the first surface 34 of the framework 12. In addition, thematerial can be manipulated so that the second surface 35 of theframework 32 has a backside network 35 a with passageways 37, distinctfrom the conduits 36.

The mass of material which is manipulated to form the framework 32 canbe any suitable material, including thermoplastic resins andphotosensitive resins, but the preferred material for use in forming theframework 32 of the present disclosure is a liquid photosensitivepolymeric resin. Likewise, the material chosen can be manipulated in awide variety of ways to form the desired framework 32, includingmechanical punching or drilling, curing the material by exposing it tovarious temperatures or energy sources, or by using a laser to cutconduits. The method of manipulating the material which will form theframework 32, of course, can depend on the material chosen and thecharacteristics of the framework 32 desired to be formed from the massof material. Preferably, the photosensitive resin is manipulated bycontrolling the exposure of the liquid photosensitive resin to light ofan activating wavelength.

Since the reinforcing structure 33 is positioned between the firstsurface 34 and at least a portion of the second surface 35 of theframework 32, the second surface 35 of the framework 32 can either,completely cover the reinforcing structure 33, cover only a portion ofthe reinforcing structure 33 or, cover no portions of the reinforcingstructure 33 and lie entirely within the interstices 39 of thereinforcing structure 33.

The conduits 36 have a channel portion 41 which lies between the conduitopenings 42 and 43. These channel portions 41 are defined by the walls44 of the conduits 36. FIGS. 2-4 show that the holes or channels 41formed by the conduits 36 extend through the entire thickness of thepapermaking belt 10. In addition, as shown in FIG. 2, the conduits 36are generally discrete. By “discrete”, it is meant that the conduits 36form separate channels, which are separated from each other by theframework 32. The conduits 36 are described as being “generally”discrete, however, because the conduits 36 may not be completelyseparated from each other along the second surface 35 of the framework32 when passageways 37 are present in the backside network 35 a.

It is preferred that the passageways 37 and the irregularities 38 aredistinct from the conduits 36 which pass through the framework 32. By“distinct” from the conduits, it is meant that the passageways 37 andthe irregularities 38 which comprise departures from the otherwisesmooth and continuous backside network 35 a of the framework 32 are tobe distinguished from the holes 41 formed by the conduits 36. In otherwords, the holes 41 formed by the conduits 36 are not intended to beclassified as passageways or surface texture irregularities.

Referring again to FIG. 1, belt 10 carries an embryonic web 18 on thefirst surface. As shown, a portion of belt 10 passes over a single slot24 d of a vacuum box 24. In operation, a vacuum is applied from a vacuumsource (not shown), which exerts pressure on the belts and the embryonicwebs 18 in the direction of the arrows shown. The vacuum removes some ofthe water from the embryonic web 18 and deflects and rearranges thefibers of the embryonic web into the conduits 36 of the framework 32.

The measurement devices 50 and an associated reading device 60 (alsoreferred to herein as receiver 60) (the receiver 60 being efficaciouslydisposed about the papermaking process) are preferably configured tomeasure or monitor any physical characteristics of the papermaking belt10 during the manufacture of paper products. The measurement devices 50may also be configured to measure and monitor physical characteristicsfor controlling and monitoring the papermaking process. Thecharacteristics that can be measured can include, e.g. belt temperature,belt deformation (e.g., tension, compression, bending moment, stress,and/or strain), belt and/or process pressure, belt acceleration(vibration), moisture, speed, pH, and the like. The measurement devices50 may transmit measurement data when proximate to the receiver 60,which may further communicate any measurement data to a control unitand/or a data acquisition system capable of processing and/or storingsuch measurement data. The measurement devices 50 may comprise atransmitter or a transceiver for communicating the measurement datawirelessly to a receiver 60. The measurement devices 50 may beremotely-read untouchably by receiver 60 by means of electromagneticradiation. Depending on the wavelength, the electromagnetic radiationused can include: radio waves, microwaves, infrared radiation, light,ultraviolet radiation, X-ray radiation, gamma radiation, and the like.Exemplary and suitable measurement devices can include those developedby the Wireless Identification and Sensing Platform of the University ofWashington. Suitable reading devices 60 are the model S9028PCL UHFreceiver manufactured by Laird Technologies.

Additionally, measurement devices 50 can be provided asmicroelectromechanical (MEMS), nanoelectromechanical (NEMS) systems,combinations thereof, and the like. Both MEMS and NEMS can be formedfrom graphene, at least in part, although other materials may be usedalternatively as would be understood by those of skill in the art. Aswould be understood by one of skill in the art, graphene is a singleatomic layer of carbon and is the strongest material known to man (wherestrength is not to be confused with hardness). It also has electricalproperties superior to the silicon used to make the chips found inmodern electronics. The combination of these properties can makegraphene an ideal material for nanoelectromechanical systems, which arescaled-down versions of microelectromechanical systems used for sensingany physical characteristics and any physical phenomena including butnot limited to temperature, vibration, and acceleration experienced bypapermaking belt 10 during use.

Due to the continuous shrinking of electrical circuits, particularlythose involved in creating and processing radio-frequency signals, theyare harder to miniaturize. These ‘off-chip’ components can take up a lotof space and electrical power in comparison to the overall size ofultra-small systems. In addition, most of these radio wave-relatedcomponents cannot be easily tuned in frequency, requiring multiplecopies to ensure the range of frequencies used for wirelesscommunication is covered. Graphene NEMS can address both problems inthat they are compact and easily integrated with other types ofelectronics. Further, their frequency can be tuned over a wide range offrequencies because of the tremendous mechanical strength of graphene.

The measurement devices 50 may also comprise identification information,such as a code, an ID number, or the like. In addition to identificationinformation, measurement devices 50 may comprise at least one otherpiece of information, which can include papermaking belt type number,manufacturer information, order information, date, order number or anyother information that can be utilized during the installation, use,maintenance, manufacture, or quality control of the papermaking belt 10or for ordering new papermaking belts 10. The measurement devices 50 maycomprise at least one memory wherein, in addition to the identificationinformation, at least one piece of additional information (such as anyphysical characteristics of papermaking belt 10 measured during use) maybe stored. The information stored in the memory can be changed duringthe process, during repair or washing of the belt 10, as well as duringstorage thereof.

The data obtained from the measurement devices 50 may be utilized incontrolling the papermaking process, choosing an appropriate belt for apapermaking process, clearing failures during the manufacture ofproducts, as well as in choosing papermaking process operatingparameters. Such an enhanced data acquisition system may thussignificantly improve the efficiency and efficacy of the papermakingprocess as well as the papermaking belt 10 itself. Collected data can beforwarded from the data acquisition system for managing the productionof, the use of, and/or the storage of the belts 10 as well as monitoringany necessary papermaking process conditions during the production ofpaper products that use papermaking belt 10.

The measurement device 50 may comprise a tag responding toradio-frequency electromagnetic radiation. Identification distances andwave transmittivity, for instance, may be influenced by using differentradio frequencies. The data acquisition system may further utilize tagsresponding to different frequencies of different sensors that can beused for measurement devices 50 (e.g., temperature, belt deformation,belt and/or process pressure, and the like). Additionally, themeasurement devices 50 may comprise a tag, a transponder containing anantenna for receiving radio-frequency electromagnetic radiation as wellas a microchip wherein the identification information is stored.Further, the measurement devices 50 may comprise a so-called RadioFrequency Identification (RFID) tag. The tag can be extremely smallthereby making it easier to position within or upon the belt 10. SuchRFID tags are inexpensive, reliable, and highly available.

Measurement device 50 can be a passive RFID tag which comprises no powersource of its own but the extremely low electric current required by itsoperation is induced by radio-frequency scanning received by the antennacontained within measurement device 50 and transmitted by the receiver60. By means of this induced current, the tag is able to transmit aresponse to an inquiry sent by the reading device. In other words, thereading device searches through (e.g., scans) the environment for a tag,and the tag transmits, for example, a measured physical characteristicof papermaking belt 10, any ID code, and/or any other relevant and/ornecessary information stored in the microchip (response) after thescanning has induced thereto the electric current necessary for thetransmission. The RFID tag may be read at a radio frequency withoutvisual communication and it may be read even through obstacles. Inaddition, exemplary RFID readers can read a plurality of measurementdevices 50, such as RFID tags, simultaneously.

The measurement devices 50 may comprise one or more portable electronicterminal devices suitable as a reading device 60. The reading device 60may be a data acquisition device, portable computer, palmtop computer,mobile telephone or another electronic device provided with thenecessary means for remote-reading a tag. The reading device 60 maycomprise a control unit included in the monitoring system.

By way of non-limiting example, measurement devices 50 can comprisethermocouples for measuring the temperature of the papermaking belt 10.Alternatively, the measurement device 50 could comprise a strain gaugesensor that would be suitable for measuring the bending moment, tension,stress, and/or strain present within papermaking belt 10. Yet still,measurement device 50 could be provided as a pressure sensor, a pHsensor, or even a wear (i.e., erosion) gauge.

If measurement device 50 is provided as a thermocouple, a thermocouplesuitable for use as a measurement device 50 could be woven into thereinforcing structure 33. Alternatively, the measurement device 50 couldbe disposed upon the reinforcing structure 33 and/or affixed to thereinforcing structure 33 by needlework or by way of adhesive. Further,measurement device 50 could be printed onto the reinforcing structure 33using 3D-printing technology, for example. In any regard, it ispreferred that measuring device 50 not have any adverse impact on theoverall permeability of the papermaking belt 10.

It is also believed that the measurement device 50 can be woven into theportion of the papermaking belt that is overlapped and re-woven to forma seam that makes papermaking belt 10 an endless loop. If it is chosento apply the measurement device 50 only at this location on thepapermaking belt 10, one of skill in the art will understand that duringuse of the papermaking belt 10, the result will be suitable measurementstaken in a highly periodic fashion. For example, if a papermaking beltis 200 feet in overall length, and during manufacturing is operated at alinear speed of 2,000 feet/minute, the seam portion of papermaking belt10 having measurement devices 50 disposed therein/thereon, can provide ameasurement at any given point in the manufacturing process every 10seconds.

Alternatively, it is believed that measurement device 50 can be providedas a portion of a bi-component filament material utilized to formreinforcing structure 33. In other words, the measurement device 50 canbe arranged as a filament that includes the measurement device 50 (andany associated electronics) as either the inner or outer portion of acoaxially formed bi-component filament or any other type of highperformance cable. In this manner, one of skill in the art willrecognize that any number of measurement devices 50 can be woven intoand incorporated as part of reinforcing structure 33 at any location, orin any number of locations, within the confines of reinforcing structure33.

Yet still, if measurement device 50 is provided as a MEMS or NEMS(discussed supra), it is believed that one of skill in the art couldincorporate such a MEMS or NEMS sensor(s) into the resin used to formthe framework 32. In this way a significant number of measurementdevices 50 can be incorporated across the papermaking belt 10 in the CD,over its length in the MD, and combinations thereof. Measurement devices50 can be disposed collinearly, sinusoidally, randomly, or in anyfashion across the CD, MD, and combinations thereof. The use of suchMEMS and/or NEMS sensors can significantly reduce any effects and/orimpact of disposing a measurement device 50 into a papermaking belt 10by reducing the amount of physical effort necessary to incorporate ameasurement device 50 into the reinforcing structure 33 or the framework32 as well as reduce the impact to the permeability of the papermakingbelt 10 due to any portions of the measurement device 10 that may bedisposed within a given conduit 36.

Process for Making a Papermaking Belt

As indicated above, the papermaking belt 10 can take a variety of forms.While the method of construction of the papermaking belt 10 isimmaterial so long as it has the characteristics required to manufacturepaper products, certain methods have been discovered to be useful. Oneexemplary and non-limiting process for making the improved papermakingbelt 10 of the present disclosure is described infra.

A preferred embodiment of an apparatus which can be used to construct apapermaking belt 10 of the present disclosure in the form of an endlessbelt is shown in schematic outline in FIG. 6. In order to show anoverall view of the entire apparatus for constructing a papermaking beltin accordance with the present disclosure, FIG. 6 was simplified to acertain extent with respect to some of the details of the process. Thedetails of this apparatus, and particularly the manner in which thepassageways 37 and the surface texture irregularities 38 are imparted tothe backside network 35 a of the second surface 35 of the framework 32are shown in the figures which follow. It should be noted at this pointthat the scale of certain elements shown may be somewhat exaggerated inthe following drawing figures.

The overall process for making the improved papermaking belt 10generally involves coating a reinforcing structure 33 having measurementdevices 50 disposed therein or thereupon with a liquid photosensitivepolymeric resin 70 when the reinforcing structure 33 is traveling over aforming unit or table 71 (or “casting surface”) 72. Alternatively, ameasurement device 50 provided as a MEMS or NEMS could be dispersedwithin the resin used to coat the reinforcing structure 33.

As shown in FIG. 6, the resin, or “the coating” 70 (with or without MEMSand/or NEMS) is applied to at least one (and preferably both) sides(s)of the reinforcing structure 33 (with or without a measuring device 50disposed therein or thereupon) so the coating 70 substantially fills thevoid areas of the reinforcing structure 33 and forms a first surface 34′and a second surface 35′. The coating 70 is distributed so that at leasta portion of the second surface 35′ of the coating is positionedadjacent the casting surface 72 of the forming unit 71. The coating 70is also distributed so that the paper-facing side 51 of the reinforcingstructure 33 is positioned between the first and second surfaces 34′ and35′ of the coating 70. In addition, as shown in FIG. 7, the coating 70is distributed so portions of the second surface 35′ of the coating arepositioned between the opaque first portion P₀₁ of the reinforcingcomponent 40 and the working surface 72 of the forming unit 71. Theportion of the coating which is positioned between the first surface 34′of the coating and the paper-facing side 51 of the reinforcing structure33 forms a resinous overburden t₀′. The thickness of the overburden t₀′can be controlled to a preselected value.

The liquid photosensitive resin 70 is then exposed to a light having anactivating wavelength (light which will cure the photosensitive liquidresin) from a light source 73 through a mask 74 which has opaque regions74 a and transparent regions 74 b and through the reinforcing structure33. The portions of the resin which have been shielded or protected fromlight by the opaque regions 74 a of the mask 74 and by the first portionP₀₁ of the reinforcing structure 33 are not cured by the exposure to thelight. The remaining portions of the resin (the unshielded portions, andthose portions that the second portion P₀₂ of the reinforcing structure33 permits the curing of) are cured. The uncured resin is then removedto leave conduits 36 which pass through the cured resin framework 32.

For convenience, the stages in the overall process are broken down intoa series of steps and examined in greater detail in the discussion whichfollows. It is to be understood, however, that the steps described beloware intended only to provide an exemplary embodiment and to assist thereader in understanding a method of making the papermaking belt of thepresent disclosure.

First Step

The first step of the process of the present disclosure is providing aforming unit 71 with a working surface 72. The forming unit 71 hasworking surface which is designated 72. Preferably, the forming unit 71is covered by a barrier film 76 which prevents the working surface 72from being contaminated with resin. The barrier film 76 also facilitatesthe removal of the partially completed papermaking belt 10′ from theforming unit 71. Generally, the barrier film 76 can be any flexible,smooth, planar material such as polypropylene, polyethylene, orpolyester sheeting. Preferably, the barrier film 76 also either absorbslight of the activating wavelength, or is sufficiently transparent totransmit such light to the working surface 72 of the forming unit 71,and the working surface 72 absorbs the light.

The barrier film 76 contacts the working surface 72 of forming unit 71and is temporarily constrained against the working surface 72. Thebarrier film 76 travels with the forming unit 71 as the forming unit 71rotates. The barrier film 76 is eventually separated from the workingsurface 72 of the forming unit 71. Preferably, the forming unit 71 isalso provided with a means for insuring that barrier film 76 ismaintained in close contact with its working surface 72. Preferably, thebarrier film 76 is held against the working surface 72.

Second Step

The second step of the process of the present disclosure is providing areinforcing structure 33, for incorporation into the papermaking belt.FIG. 7 shows that the reinforcing structure 33 has a paper-facing side51, a machine-facing side 52 opposite the paper-facing side 51,interstices 39, and a reinforcing component 40 comprised of a pluralityof structural components 40 a. A first portion P₀₁ of the reinforcingcomponent 40 can have a first opacity 0 ₁ and a second portion P₀₂ ofthe reinforcing component 40 can have a second opacity 0 ₂ less than thefirst opacity 0 ₁. The first opacity 0 ₁ is preferably sufficient tosubstantially prevent curing of the photosensitive resinous materialwhen the photosensitive resinous material is in its uncured state andthe first portion is positioned between the photosensitive resinousmaterial and an actinic light source 73. The second opacity 0 ₂ ispreferably sufficient to permit curing of the photosensitive resinousmaterial. Preferably, the reinforcing structure 33 is a woven,multilayer fabric.

If a measurement device 50 is provided, it could be woven into thereinforcing structure 33. Alternatively, the measurement device 50 couldbe disposed upon the reinforcing structure 33 and/or affixed to thereinforcing structure 33 by needlework or by way of adhesive. Further,measurement device 50 could be printed onto the reinforcing structure 33using 3D-printing technology, for example.

It is also believed that the measurement device 50 can be woven into theportion of the papermaking belt that is overlapped and re-woven to forma seam that makes papermaking belt 10 an endless loop. Alternatively, itis believed that measurement device 50 can be provided as a portion of abi-component filament material utilized to form reinforcing structure33. In other words, the measurement device 50 can be arranged as afilament that includes the measurement device 50 (and any associatedelectronics) as either the inner or outer portion of a coaxially formedbi-component filament or any other type of high performance cable. Inthis manner, one of skill in the art will recognize that any number ofmeasurement devices 50 can be woven into and incorporated as part ofreinforcing structure 33 at any location, or in any number of locations,within the confines of reinforcing structure 33.

Since the preferred papermaking belt 10 is in the form of an endlessbelt, the reinforcing structure 33 should also be an endless belt sincethe papermaking belt 10 is constructed around the reinforcing structure33. As illustrated in FIG. 6, the reinforcing structure 33 which hasbeen provided is arranged so that it travels in the direction indicatedby directional arrow Dl. It is to be understood that in the apparatusused to make the papermaking belt of the present disclosure, there areconventional guide rolls, return rolls, drive means, support rolls andthe like which are not shown or identified with specificity in FIG. 6.

Third Step

The third step in the process of the present disclosure is bringing atleast a portion of the machine-facing side 52 of the reinforcingstructure 33 into contact with the working surface 72 of the formingunit 71 (or more particularly in the case of the embodiment illustrated,traveling the reinforcing structure 33 over the working surface 72 ofthe forming unit 71). At least a portion of the machine-facing side 52of the reinforcing structure 33 is brought into contact with the barrierfilm 76 so that the barrier film 76 is interposed between thereinforcing structure 33 and the forming unit 72.

Fourth Step

The fourth step in the process is applying a coating of liquidphotosensitive resin 70 to at least one side of the reinforcingstructure 33 having the measurement devices 50 incorporated therein ordisposed thereupon. Generally, the coating 70 is applied so that thecoating 70 substantially fills the void areas 39 a of the reinforcingstructure 33 (the void areas are defined below). The coating 70 is alsoapplied so that it forms a first surface 34′ and a second surface 35′.The coating 70 is distributed so that at least a portion of the secondsurface 35′ of the coating 70 is positioned adjacent the working surface72 of the forming unit 71. The coating 70 is distributed so that thepaper-facing side 51 of the reinforcing structure 33 is positionedbetween the first and second surfaces 34′ and 35′ of the coating 70. Theportion of the coating which is positioned between the first surface 34′of the coating and the paper-facing side 51 of the reinforcing structure33 forms a resinous overburden t₀ ‘. The coating 70 is also distributedso that portions of the second surface 35’ of the coating 70 arepositioned between the first portion P₀₁ of the reinforcing component 40and the working surface 72 of the forming unit 71.

Suitable photosensitive resins can be readily selected from the manyavailable commercially. Resins which can be used are materials, usuallypolymers, which cure or cross-link under the influence of actinicradiation, usually ultraviolet (UV) light. Such a resin can be providedwith measurement devices 50 provided as NEMS contained therein.

The application of resin 70 by the extrusion header 79 is employed inconjunction with the application of a second coating of liquidphotosensitive resin 70 at a second stage by a nozzle 80 locatedadjacent to the place where the mask 74 is introduced into the system.The nozzle 80 applies the second coating of liquid photosensitive resin70 to the paper-facing side 51 of the reinforcing structure 33. It isnecessary that liquid photosensitive resin 70 be evenly applied acrossthe width of reinforcing structure 33 and that the requisite quantity ofmaterial be worked through interstices 39 to substantially fill the voidareas 39 a of the reinforcing structure 33.

It is also believed that the measurement device 50 can be placed into aportion of the resin that has been applied to the papermaking belt 10.In other words, the measurement device 50 can be pushed into the resinforming the papermaking belt so that the resin can envelop themeasurement device 50 prior to any curing process. In this way, themeasurement device 50 (and any associated electronics) can beincorporated at any location, or in any number of locations, within theconfines of papermaking belt 10.

Fifth Step

The fifth step involves control of the thickness of the overburden t₀′of the resin coating 70 to a preselected value. In the preferredembodiment of the belt making apparatus shown in the drawings, this steptakes place at approximately the same time, i.e., simultaneously, withthe second stage of applying a coating of liquid photosensitive resin tothe reinforcing structure 33. The preselected value of the thickness ofthe overburden corresponds to the thickness desired for the papermakingbelt 10 and follows from the expected use of the papermaking belt 10.

Sixth Step

The sixth step in the process of this disclosure can be considered aseither a single step or as two separate steps which comprise: (1)providing a mask 74 having opaque 74 a and transparent regions 74 b inwhich the opaque regions 74 a together with the transparent regions 74 bdefine a preselected pattern in the mask; and (2) positioning the mask74 between the coating of liquid photosensitive resin 70 and an actiniclight source 73 so that the mask 74 is in contacting relation with thefirst surface 34′ of the coating of liquid photosensitive resin 70. Thepurpose of the mask 74 is to protect or shield certain areas of theliquid photosensitive resin 70 from exposure to light from the actiniclight source. It follows that if certain areas are shielded, it followsthat any liquid photosensitive resin 70 in those areas that are notshielded will be exposed later to activating light and will be cured.

The mask 74 can be made from any suitable material which can be providedwith opaque regions 74 a and transparent regions 74 b. A material in thenature of a flexible photographic film is suitable for use as a mask 74.The flexible film can be polyester, polyethylene, or cellulosic or anyother suitable material. The opaque regions 74 a should be opaque tolight which will cure the photosensitive liquid resin. The opaqueregions 74 a can be applied to mask 74 by any convenient means such asby a blue printing (or ozalid processes), or by photographic or gravureprocesses, flexographic processes, or rotary screen printing processes.

It should be understood that if one of skill in the art provides themeasurement devices 50 as MEMS and/or NEMS, one could incorporate themeasurement devices 50 into the treatments and/or solutions used tocreate the mask 74. This could allow for the measurement devices 50 tobe effectively transferred to the surface of the resulting papermakingbelt 10. In this case it would be preferred that such a measurementdevice 50 be transparent to the actinic radiation used in the curingprocess so not to interfere with the resin curing process.

Seventh Step

The seventh step of the process of this disclosure comprises curing theunshielded portions of liquid photosensitive resin in those regions leftunprotected by the transparent regions 74 b of the mask 74 and curingthose portions of the coating 70 that the second portion P₀₂ of thereinforcing structure 33 permits the curing of, and leaving the shieldedportions and those portions of the coating positioned between the firstportion P₀₁ of the reinforcing structure 33 and the working surface 72of the forming unit 71 uncured by exposing the coating of liquidphotosensitive resin 70 to light of an activating wavelength from thelight source 73 through the mask 74. When the barrier film 76 and thereinforcing structure 33 are still adjacent the forming unit 71, theliquid photosensitive resin 70 is exposed to light of an activatingwavelength which is supplied by an exposure lamp 73.

The exposure lamp 73, in general, is selected to provide illuminationprimarily within the wavelength which causes curing of the liquidphotosensitive resin 70. That wavelength is a characteristic of theliquid photosensitive resin 70. Any suitable source of illumination,such as mercury arc, pulsed xenon, electrode-less, and fluorescentlamps, can be used. As described above, when the liquid photosensitiveresin 70 is exposed to light of the appropriate wavelength, curing isinduced in the exposed portions of the resin 70. Curing is generallymanifested by a solidification of the resin in the exposed areas.Conversely, the unexposed regions remain fluid. The intensity of theillumination and its duration depend upon the degree of curing requiredin the exposed areas.

In the preferred embodiment of the present disclosure, the angle ofincidence of the light is collimated to better cure the photosensitiveresin in the desired areas, and to obtain the desired angle of taper inthe walls 44 of the finished papermaking belt 10. Other means ofcontrolling the direction and intensity of the curing radiation, includemeans which employ refractive devices (i.e., lenses), and reflectivedevices (i.e., mirrors). The preferred embodiment of the presentdisclosure employs a subtractive collimator (i.e., an angulardistribution filter or a collimator which filters or blocks UV lightrays in directions other than those desired). Any suitable device can beused as a subtractive collimator. A dark colored, preferably black,metal device formed in the shape of a series of channels through whichlight directed in the desired direction may pass is preferred. In thepreferred embodiment of the present disclosure, the collimator is ofsuch dimensions that it transmits light so the resin network, whencured, has a projected surface area of about 20-50% on the topside ofthe papermaking belt 10 and about 50-80% on the backside.

Eighth Step

The eighth step in the process in the present disclosure is removingsubstantially all of the uncured liquid photosensitive resin from thepartially-formed composite belt 10′ to leave hardened resin framework 32around at least a portion of the reinforcing structure 33. In this step,the resin which has been shielded from exposure to light is removed fromthe partially-formed composite belt 10′ to provide the framework 32 witha plurality of conduits 36 in those regions which were shielded from thelight rays by the opaque regions 74 a of the mask 74 and passageways 37that provide surface texture irregularities 38 in the backside network35 b of the framework 32.

As shown in FIG. 25, at a point in the vicinity of the mask guide roll82, the mask 74 and the barrier film 76 are physically separated fromthe partially-formed composite belt 10′. The composite of thereinforcing structure 33 and the partly cured resin 70 travels to thevicinity of the first resin removal shoe 83 a where a vacuum is toremove a substantial quantity of the uncured liquid photosensitive resinfrom the composite belt 10′.

As the composite belt 10′ travels farther, it is brought into thevicinity of resin wash shower 84 and resin wash station drain 85 atwhich point the composite belt 10′ is thoroughly washed with water orother suitable liquid to remove essentially all of the remaining uncuredliquid photosensitive resin which is discharged from the system throughresin wash station drain 85.

The composite belt 10′ is then subjected to a second exposure of lightof the activating wavelength by post cure UV light source 73 a. Thissecond exposure, however, takes place when the composite belt 10′ issubmerged in a bath 88. The process continues until such time as theentire length of reinforcing structure 33 has been treated and convertedinto the papermaking belt 10. At the second resin removal shoe 83 b, anyresidual wash liquid and uncured liquid resin is removed from thecomposite belt 10′ by the application of vacuum.

It is also believed that the measurement device 50 can be placed intoany portion of the cured resin remaining on the papermaking belt 10. Inother words, a recess can be formed within the confines of thepapermaking belt 10 and the measurement device 50 disposed therein. Byway of non-limiting example only, a slot can be excised into the surfaceof the papermaking belt 10 and a measurement device 50 placed within thegeometry of the slot so that the measurement device 50 (and anyassociated electronics) remains disposed below the surface of thepapermaking belt 10. Resin can then be applied and cured into the slotso formed thereby covering the measurement devices 50.

The Papermaking Process

The papermaking process which utilizes the improved papermaking belt 10of the present disclosure is described below, although it iscontemplated that other processes may also be used to make the paperproducts described herein. Returning again to FIG. 1, a simplified,schematic representation of one embodiment of a continuous papermakingmachine useful in the practice of the papermaking process of the presentdisclosure is shown.

First Step

The first step in the practice of the papermaking process of the presentdisclosure is the providing of an aqueous dispersion of papermakingfibers 14. The aqueous dispersion of papermaking fibers 14 is providedto a head box 13. The aqueous dispersion of papermaking fibers 14supplied by the head box 13 is delivered to a forming belt, such as theFourdrinier wire 15 for carrying out the second step of the papermakingprocess. The Fourdrinier wire 15 is propelled in the direction indicatedby directional arrow A by a conventional drive means which is not shownin FIG. 1.

Second Step

The second step in the papermaking process is forming an embryonic web18 of papermaking fibers on a foraminous surface from the aqueousdispersion 14 supplied in the first step. After the embryonic web 18 isformed, it travels with Fourdrinier wire 15 and is brought into theproximity of a second papermaking belt, the papermaking belt 10 of thepresent disclosure.

Third Step

The third step in the papermaking process is contacting (or associating)the embryonic web 18 with the paper-contacting side 11 of thepapermaking belt 10 of the present disclosure. The purpose of this thirdstep is to bring the embryonic web 18 into contact with thepaper-contacting side of the papermaking belt 10 on which the embryonicweb 18, and the individual fibers therein, will be subsequentlydeflected, rearranged, and further dewatered. The Fourdrinier wire 15brings the embryonic web 18 into contact with, and transfers theembryonic web 18 to the papermaking belt 10 of the present disclosure inthe vicinity of vacuum pickup shoe 24 a.

As illustrated in FIG. 1, the papermaking belt 10 of the presentdisclosure travels in the direction indicated by directional arrow B.The papermaking belt 10 passes around return rolls 19 a and 19 b,impression nip roll 20, return rolls 19 c, 19 d, 19 e and 19 f, andemulsion distributing roll 21.

It can be preferred that receivers 60 be staged around that portion ofthe papermaking process where the papermaking belt 10 of the presentdisclosure is used. In particular it could be advantageous to positionthe receiver(s) at locations that follow a heating process. For example,it may be advantageous to position receivers 60 after pre-dryer 26. Inthis manner, the temperature of the papermaking belt 10 havingmeasurement devices 50 disposed therein or thereupon in the form ofthermocouples, can provide in situ feed-back of actual, real-timetemperatures experienced by the papermaking belt 10. By way ofnon-limiting example only, if a papermaking belt 10, havingthermocouples disposed therein, experiences a papermaking processtemperature that is higher than required or allowed upon exitingpre-dryer 26, the temperature of the pre-dryer 26 can be accordinglyadjusted in order to reduce energy costs, produce paper products withinspecification, and preserve papermaking belt 10 life by reducing or evenpreventing the occurrence of micro-fractures or oxidation of the resinforming the papermaking belt 10 that causes the papermaking belt 10 tobecome brittle. All of these beneficial end results can result in lowermanufacturing costs for paper products.

Fourth Step

The fourth step in the papermaking process involves applying a fluidpressure differential of a suitable fluid to the embryonic web 18 with avacuum source to deflect at least a portion of the papermaking fibers inthe embryonic web 18 into the conduits 36 of the papermaking belt 10 andto remove water from the embryonic web 18 through the conduits 36 toform an intermediate web 25 of papermaking fibers. The deflection alsoserves to rearrange the fibers in the embryonic web 18 into the desiredstructure.

Either at the time the fibers are deflected into the conduits 36 orafter such deflection occurs, water is removed from the embryonic web 18through the conduits 36. Water removal occurs under the action of thefluid pressure differential. It is important, however, that there beessentially no water removal from the embryonic web 18 prior to thedeflection of the fibers into the conduits 36. As an aid in achievingthis condition, at least those portions of the conduits 36 surrounded bythe paper side network 34 a, are generally isolated from one another.This isolation, or compartmentalization, of conduits 36 is of importanceto insure that the force causing the deflection, such as an appliedvacuum, is applied relatively suddenly and in a sufficient amount tocause deflection of the fibers. This is to be contrasted with thesituation in which the conduits 36 are not isolated. In this lattersituation, vacuum will encroach from adjacent conduits 36 which willresult in a gradual application of the vacuum and the removal of waterwithout the accompanying deflection of the fibers.

Fifth Step

The fifth step is traveling the papermaking belt 10 and the embryonicweb 18 over the vacuum source described in the fourth step. The belt 10carries the embryonic web 18 on its paper-contacting side 11 over thevacuum source. At least a portion of the textured backside 12 of thebelt 10 is generally in contact with the surface of the vacuum source asthe belt 10 travels over the vacuum source. Following the application ofthe vacuum pressure and the traveling of the papermaking belt 10 and theembryonic web 18 over the vacuum source, the embryonic web 18 is in astate in which it has been subjected to a fluid pressure differentialand deflected but not fully dewatered, thus it is now referred to asintermediate web 25.

It could be advantageous to position the receiver(s) 60 at locationsthat follow such a vacuum process. For example, it may be advantageousto position receivers 60 after the vacuum source described supra. Inthis manner, the temperature of the papermaking belt 10 havingmeasurement devices 50 disposed therein or thereupon in the form of astrain gauge can provide in situ feed-back of actual, real-time bendingmoment, stress, strain, erosion, and or combinations thereof experiencedby the papermaking belt 10. By way of non-limiting example only, if apapermaking belt 10, having a strain gauge disposed therein, experiencesa papermaking stress and/or strain that is higher than required orallowed upon exiting the vacuum source, the vacuum pressure applied bythe vacuum source can be accordingly adjusted in order to reduce energycosts, produce paper products within specification, and preservepapermaking belt 10 life by reducing or even preventing the occurrenceof micro-fractures or oxidation of the resin forming the papermakingbelt 10 that causes the papermaking belt 10 to become brittle. All ofthese beneficial end results can result in lower manufacturing costs forpaper products.

Sixth Step

The sixth step in the papermaking process is an optional step whichcomprises drying the intermediate web 25 to form a pre-dried web ofpapermaking fibers. Any convenient means conventionally known in thepapermaking art can be used to dry the intermediate web 25. For example,flow-through dryers, non-thermal, capillary dewatering devices, andYankee dryers, alone and in combination, are satisfactory.

After leaving the vicinity of vacuum box 24, the intermediate web 25,which is associated with the papermaking belt 10, passes around thereturn roll 19 a and travels in the direction indicated by directionalarrow B. The intermediate web 25 then passes through optional pre-dryer26. This pre-dryer 26 can be a conventional flow-through dryer (hot airdryer) well known to those skilled in the art.

Receivers 60 can be staged around that portion of the papermakingprocess immediately after optional pre-dryer 26. This can provide for insitu feed-back of actual, real-time temperatures experienced by thepapermaking belt 10 during exposure to pre-dryer 26 by measurementdevices 50 disposed therein or thereupon. If a papermaking belt 10having, for example, thermocouples disposed therein, experiences apre-dryer 26 process temperature that is higher than required orallowed, the temperature of the pre-dryer 26 can be accordingly adjustedin order to reduce or even prevent the occurrence of micro-fractures oroxidation of the resin forming the papermaking belt 10 that causes thepapermaking belt 10 to become brittle.

Seventh Step

The seventh step in the papermaking process provides for impressing thepaper side network 34 a of the papermaking belt 10 of the presentdisclosure into the pre-dried web by interposing the pre-dried web 27between the papermaking belt 10 and an impression surface to form animprinted web of papermaking fibers.

As illustrated in FIG. 1 when the pre-dried web 27 then passes throughthe nip formed between the impression nip roll 20 and the Yankee drierdrum 28. As the pre-dried web 27 passes through this nip, the networkpattern formed by the paper side network 34 a on the paper-contactingside 11 of the papermaking belt 10 is impressed into pre-dried web 27 toform imprinted web 29.

By way of non-limiting example, receivers 60 can preferably be stagedaround and/or proximate to those portions of the papermaking processwhere the papermaking belt 10 is subjected to a compressionary process.For example, a receiver could be staged at that portion of thepapermaking process that follows contact of the papermaking belt 10 inthe nip formed between impression nip roll 20 and the Yankee drier drum28. By way of example only, if a papermaking belt 10, having pressuresensors disposed therein, experiences a higher or lower pressure thanwhat is required, allowed, or the most efficacious to effect transfer ofthe paper web from one portion of the process to another, theappropriate nip pressure can be accordingly adjusted. Additionally,other critical parameters can be observed and understood in this nip.This can include the nip gap profile uniformity, nip loading profileuniformity, PLI loading uniformity, nip width/belt age profiles, and nippressure uniformity.

Additionally, receivers 60 can also preferably be staged around thoseportions of the papermaking process where the papermaking belt 10 issubjected to other process forces. By way of non-limiting example, itcan be seen in real-time if the papermaking belt 10 is experiencing anyPoisson contraction effects resulting from thermal or mechanical inducedover-stretching of the papermaking belt 10. Additionally, equipmentmisalignments can be detected by monitoring the pressures observed bythe papermaking belt 10. Other critical parameters can be observed andunderstood. This can include the nip gap profile uniformity, nip loadingprofile uniformity, PLI loading uniformity, nip width/belt age profiles,and nip pressure uniformity. And measurement device 10 could be achemical sensor to monitor water quality or running pH conditions in thepapermaking process. Process anomalies can be detected by providing ameasurement device 10 in the form of a plurality of strain gaugesdisposed within the papermaking belt 10 across the CD (e.g., the centerand edges of papermaking belt 10) in order to understand, observe, andcontrol the bending moment (i.e., bow deflection and/or skew)experienced by the papermaking belt 10 in process equipment (e.g., a Mt.Hope roll). Additionally, providing measurement device 10 as anaccelerometer would be a unique method to understand, observe, andcontrol speed changes between driven rolls of process equipment as wellas adjust speeds for drive tuning.

These examples of the usefulness of the unique papermaking belt 10 canresult in a reduction in energy costs, increase papermaking belt 10 lifeas well as increase the life of the contacted components by reducingwear on the contacting surfaces. It is reasonably believed, withoutbeing drawn to any particular theory, that papermaking belt 10 life canbe at least doubled by reducing the detrimental effects experienced bythe resin. All of these end results can result in lower manufacturingcosts for paper products.

In any regard, the data measured by the measuring device 50 can beincorporated into a database that can be used to establish a papermakingbelt 10 profile or a papermaking process profile. The collected data canbe compared to an idealized or modeled set-point profile.

Additionally, the data, and/or the profile can be looped back into thepapermaking process. This can allow the adjustment of processtemperatures, nip pressures, and the like in situ. Alternatively, thedata and/or profile can be used to provide a historical perspective onpapermaking belt 10 performance benchmarking over time as well asexpected papermaking belt 10 life. Further, the data and/or profile canbe used to manage process spikes such as web breakages, e-stops, andpower outages that can cause manufacturing equipment to stop but notsignificantly reduce operating temperatures instantaneously.

Eighth Step

The eighth step in the papermaking process is drying the imprinted web29. The imprinted web 29 separates from the papermaking belt 10 of thepresent disclosure after the paper side network 34 a is impressed intothe web to from imprinted web 29. As the imprinted web 29 separates fromthe papermaking belt 10 of the present disclosure, it is adhered to thesurface of Yankee dryer drum 28 where it is dried.

Ninth Step

The ninth step in the papermaking process is the foreshortening of thedried web (imprinted web 29). This ninth step is an optional, but highlypreferred, step. Foreshortening refers to the reduction in length of adry paper web which occurs when energy is applied to the dry web in sucha way that the length of the web is reduced and the fibers in the webare rearranged with an accompanying disruption of fiber-fiber bonds.Foreshortening can be accomplished in any of several well-known ways.The most common, and preferred, method is creping.

In the creping operation, the dried web 29 is adhered to a surface andthen removed from that surface with a doctor blade 30. The surface towhich the web is usually adhered also functions as a drying surface.Typically, this surface is the surface of a Yankee dryer drum 28. Thepaper web 31 is then ready for use.

All publications, patent applications, and issued patents mentionedherein are hereby incorporated in their entirety by reference. Citationof any reference is not an admission regarding any determination as toits availability as prior art to the claimed invention.

The dimensions and/or values disclosed herein are not to be understoodas being strictly limited to the exact numerical values recited.Instead, unless otherwise specified, each such dimension and/or value isintended to mean both the recited dimension and/or value and afunctionally equivalent range surrounding that dimension and/or value.For example, a dimension disclosed as “40 mm” is intended to mean “about40 mm”.

Every document cited herein, including any cross referenced or relatedpatent or application, is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A method for extending the life of a papermakingbelt by adjusting a papermaking process for producing rolls ofconvolutely wound web material having a machine direction (MD) and across-machine direction (CD) coplanar and orthogonal thereto, saidmethod improving the operating life of said papermaking belt usedtherefor, the process for extending the life of a papermaking beltcomprising the steps of: (a) providing a foraminous papermaking belthaving a discrete measuring device disposed therein; (b) providing apapermaking machine, said papermaking machine having at least oneheating process, said heating process having a heating processset-point, said foraminous papermaking belt being integral with saidpapermaking machine; (c) depositing an aqueous dispersion of papermakingfibers upon a surface of said papermaking belt; (d) dewatering saidaqueous dispersion of papermaking fibers while disposed upon saidsurface of said foraminous papermaking belt by causing said foraminouspapermaking belt and said aqueous dispersion of papermaking fibersdisposed thereon to traverse through said heating process, said discretemeasuring device measuring a temperature of said heating process; (e)causing said foraminous papermaking belt to traverse past a receiver,said receiver being in wireless communicating engagement with saiddiscrete measuring device when said discrete measuring device isproximate said receiver, said discrete measuring device being capable ofwirelessly transmitting information to said receiver, said informationcomprising data relating to said temperature of said heating processduring said dewatering step; and, (f) changing said heating processset-point according to said measurement of said temperature of saidheating process of said dewatering step.
 2. The method of claim 1further comprising the step of collecting said data to form apapermaking belt profile.
 3. The method of claim 2 further comprisingthe step of changing said heating process set-point according to saidpapermaking belt profile.
 4. The method of claim 1 further comprisingthe step of collecting said data to form a papermaking process profile.5. The method of claim 4 further comprising the step of changing saidheating process set-point according to said papermaking process profile.6. The method of claim 1 further comprising the step of providing saidforaminous papermaking belt as a continuous loop, said continuous loopbeing provided within said papermaking process to provide periodiccommunicating engagement with said receiver.
 7. The method of claim 1further comprising the step of providing said discrete measuring deviceas a thermocouple.
 8. A method for extending the life of a papermakingbelt by adjusting a papermaking process for producing rolls ofconvolutely wound web material having a machine direction (MD) and across-machine direction (CD) coplanar and orthogonal thereto, saidmethod improving the operating life of said papermaking belt usedtherefor, the process for extending the life of a papermaking beltcomprising the steps of: (a) providing a foraminous papermaking belthaving a discrete measuring device disposed therein; (b) providing apapermaking machine, said papermaking machine having at least onecompressionary process, said compressionary process having acompressionary process set-point, said foraminous papermaking belt beingintegral with said papermaking machine; (c) depositing an aqueousdispersion of papermaking fibers upon a surface of said papermakingbelt; (d) dewatering said aqueous dispersion of papermaking fibers whiledisposed upon said surface of said foraminous papermaking belt bycausing said foraminous papermaking belt and said aqueous dispersion ofpapermaking fibers disposed thereon to traverse through saidcompressionary process, said discrete measuring device measuring atleast one compressionary force of said compressionary process; (e)causing said foraminous papermaking belt to traverse past a receiver,said receiver being in wireless communicating engagement with saiddiscrete measuring device when said discrete measuring device isproximate said receiver, said discrete measuring device being capable ofwirelessly transmitting information to said receiver, said informationcomprising data relating to said pressure of said compressionary processduring said dewatering step; and, (f) changing said compressionaryprocess set-point according to said measurement of said pressure of saidcompressionary process of said dewatering step.
 9. The method of claim 8further comprising the step of collecting said data to form apapermaking belt profile.
 10. The method of claim 9 further comprisingthe step of changing said compressionary process set-point according tosaid papermaking belt profile.
 11. The method of claim 9 furthercomprising the step of collecting said data to form a papermakingprocess profile.
 12. The method of claim 11 further comprising the stepof changing said compressionary process set-point according to saidpapermaking process profile.
 13. The method of claim 9 furthercomprising the step of providing said foraminous papermaking belt as acontinuous loop, said continuous loop being provided within saidpapermaking process to provide periodic communicating engagement withsaid receiver.
 14. The method of claim 9 further comprising the step ofproviding said discrete measuring device as a pressure sensor.
 15. Amethod for extending the life of a papermaking belt by adjusting apapermaking process for producing rolls of convolutely wound webmaterial having a machine direction (MD) and a cross-machine direction(CD) coplanar and orthogonal thereto, said method improving theoperating life of said papermaking belt used therefor, the process forextending the life of a papermaking belt comprising the steps of: (a)providing a foraminous papermaking belt having a discrete measuringdevice disposed therein; (b) providing a papermaking machine, saidpapermaking machine having at least one papermaking belt deformationprocess, said papermaking belt deformation process having a papermakingbelt deformation characteristic set-point, said foraminous papermakingbelt being integral with said papermaking machine; (c) depositing anaqueous dispersion of papermaking fibers upon a surface of saidpapermaking belt; (d) dewatering said aqueous dispersion of papermakingfibers while disposed upon said surface of said foraminous papermakingbelt by causing said foraminous papermaking belt and said aqueousdispersion of papermaking fibers disposed thereon to traverse throughsaid papermaking belt deformation process, said discrete measuringdevice measuring at least one papermaking belt deformationcharacteristic of said papermaking belt deformation process; (e) causingsaid foraminous papermaking belt to traverse past a receiver, saidreceiver being in wireless communicating engagement with said discretemeasuring device when said discrete measuring device is proximate saidreceiver, said discrete measuring device being capable of wirelesslytransmitting information to said receiver, said information comprisingdata relating to said papermaking belt deformation characteristic ofsaid papermaking belt deformation process during said dewatering step;and, (f) changing said papermaking belt deformation characteristicprocess set-point according to said measurement of said pressure of saidpapermaking belt deformation process of said dewatering step.
 16. Themethod of claim 15 further comprising the step of collecting said datato form a papermaking belt profile.
 17. The method of claim 16 furthercomprising the step of changing said papermaking belt deformationcharacteristic process set-point according to said papermaking beltprofile.
 18. The method of claim 1 further comprising the step ofcollecting said data to form a papermaking process profile.
 19. Themethod of claim 4 further comprising the step of changing saiddeformation characteristic process set-point according to saidpapermaking process profile.
 20. The method of claim 1 furthercomprising the step of providing said discrete measuring device as astrain gauge.